In producing petroleum and other useful fluids from production walls, it is generally known to provide a submergible pumping system for raising the fluids collected in a well. Production fluids enter a wellbore via perforations formed in a well casing adjacent a production formation. Fluids contained in the formation collect in the wellbore and may be raised by the submergible pumping system to a collection point above the earth's surface.
In a conventional bottom intake electric submergible pumping system, the system includes several components, such as a submergible electrical motor that supplies energy to a submergible pump. The system may further include a motor protector for isolating the motor from well fluids. A motor connector may also be used to provide a connection between the electrical motor and an electrical power supply. These and other components may be combined in the overall submergible pumping system.
Conventional submergible pumping systems are suspended within a wellbore by support tubing or by a cable. Power is supplied to the submergible electric motor by a power cable that is banded to the cable or support tubing. The banding is required because otherwise the unsupported weight of the power cable can damage or break the power cable. Coiled tubing is also used to install electric submergible pumping systems into a well. Coiled tubing provides a relatively fast and uninterrupted method for installation and retrieval of the pumping system. With coiled tubing, the power cable is either banded to the outside of the coiled tubing or disposed internally within the hollow interior formed by the coiled tubing.
Existing power cables may contain conductors for powering the motor, typically three conductors. Any other inputs to the electric submergible pumping system must be provided by a separate line, typically banded to the outside of the tubing, support cable, or coiled tubing. This, of course, leaves the additional input or control line susceptible to damage due to its location external to the submergible pumping system and system support, e.g., coiled tubing. Consequently, it would be advantageous to combine coiled tubing with an internal power cable and additional control line or control lines disposed within the hollow interior of the coiled tubing. The control line could be used to supply hydraulic fluid for the control of devices, such as a hydraulically actuated integral packer. It also could be used to supply chemical treatments into the production fluid, such as corrosion control or scale inhibitor fluids, or to provide electrical or optical inputs to additional devices or sensors within the submergible pumping system.